Questions and postings pertaining to the usage of ImageMagick regardless of the interface. This includes the command-line utilities, as well as the C and C++ APIs. Usage questions are like "How do I use ImageMagick to create drop shadows?".

When I remove white border and scale it down to 1000 pixels in height with "convert" the output is almost not smaller then the original. If I do the same with GIMP, if gets a lot smaller. Here are the results:

If you start with an 8-bit total color image and resize it, you will introduce new colors so that you end up with 24-bit color. This increases the file size. You need to convert the result back to 8-bit color.

returns other than '0 (0)', it means they are different. I guess you use 'image -> scale image' dialog with the default Cubic setting in Gimp, that use different method for resizing image. So try -scale instead of -resize in IM command. It will generate closer size file to gimp.